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美国是世界上林业发达的国家之一。现有林地面积达305万平方公里,约占全国总面积的三分之一。美国林业发达,其主要原因在于重科学,重教育,重经营管理,林业受到全社会的重视。美国人视林业为人类赖以生存的环境的维持者和保护者。他们经营林业的第一目的,是为了给人类和动植物建立一个优良的生态环境,即所谓森林的社会公益效能,而第二目的才是提供木材和林副产品等有形产物。专家们认为,森林的美化环境,维护生态平衡,防止和减轻自然灾害等无形产物的经济价值,是有形产物的十倍。这种观点已成为美国经营林业的出发点。目前,美国的森林公园和各种自然保护区逐年增多,社会用材需要已不再作为采伐量的主要考虑因素。美国林业科学相当发达。商品用材林经营,如同农作物经营一样,进行集约经营管理。由于科学育林,美国的商品用材林地的单位面积生长量和采伐运输劳动生产率,分别为每年每公顷3.3立方米和每人每年3,000立方米;而我国的相应指标仅为2.1立方米和124立方米。
The United States is one of the countries with developed forestry in the world. The existing forest area of 3.05 million square kilometers, accounting for about one-third of the total area. The United States developed forestry, the main reason is that science, education, heavy management, forestry by the whole society’s attention. Americans regard forestry as the preserve and protector of the environment upon which mankind depends. The first purpose of their forestry is to establish an excellent ecological environment for humans and animals and plants, the so-called social welfare of forests. The second purpose is to provide tangible products such as timber and forest by-products. Experts believe that the beautification of the environment, maintaining ecological balance, preventing and mitigating the economic value of intangible products such as natural disasters are ten times as much as tangible products. This view has become the starting point for the United States to run forestry. At present, forest parks and various nature reserves in the United States have been increasing year by year, and the need for social timber is no longer the main consideration for harvesting. The United States forestry science is quite developed. Timber forest management of goods, as the same as the crop management, intensive management. As a result of scientific forest cultivation, the unit area growth and harvesting labor productivity of commercial timber land in the United States are 3.3 cubic meters per hectare per year and 3,000 cubic meters per person per year, respectively; while the corresponding indicators for our country are only 2.1 cubic meters and 124 cubic meters .